Centrifugal pump.



W1 PFA/rss ES '17. NEUMANN. GEN'IRIFUG-AL PUMP. APPLIOATION FILED Mu 17,

Patented Aug. 17, 1909.

Unire raras namur carica.

FRITZ NEUMAN'N, OF NUREMBERG, GERMANY.

CENTRIFUGAL PUMP.

l Specification of Letters Eatent.

Patented Aug. 17, 1909.

Appiieauon sied nay 17, 1907. serial. No. 374,272.

i is a specification.

A centrifugal pump, if the guide vanes a throttle valve. Such a 'regulation causes however considerable losses, so that the fall in the amount of power necessaryfor oper-t ating .the centrifugal pump4 is hardly appreciable. in spite of the li'educed quantity l.of water delivered. If the centrifugal pump be only periodically regulated, that is to say l if a different quantityV of` water from that for which the pump is normally regulated be required only for short intervals of time, this drawback is not so apparent, as if a reduced flowof water is requiredr to be delivered/ by the pump for weeks and months together.- This drawback, which produces an extremely low eiiciency in centrifugal pumps when throttled, is in practice so deleteriously noticeable that centrifugal pumps are considered quite unsuitable for various` operations.

Efforts have indeed already been made to construct centrifugal pumps so as to be capable of being regulated 'and to adjust the size of the guide apparatus and the normal admission of the4 guide vanes either by ar ranging pivotal guide'vanes or displaceablyv mounting the rotor within guide apparatus lying side byside and varying in size. All these regulating devices however make the construction of centrifugal pumps very in volved and expensive and may also easily give rise to interruptions' of working.

Now this invention has for its object to construct centrifugal pumps so as to be partially regulata-ble and yet of very simple construction and Vapplicable forpurposes in which different quantities of water other than vthat for which the pump is normally designed are frequently required for longl periods. This is attained by the pump bcing provided with a releasably mounted guide apparatus inserted in an annular pas-` sage adapted to be closed, which guide apparatus may be removed without taking a bearing apart and replaced for the purpose of regulating the quantity of water to be delivered` by means of a guide apparatus provided with vanes or blades of the necessary width for delivering various quantities of water. A centrifugal pump of this kind .is shown in the accompanying drawings Figure l being a vertical longitudinal section; and Fig. 2 al front 'view of vthe halves of I two guide apparatus with vanes or blades of different width with the vanes or blades in are not displaceable, can only' be reguilated as regards the quantity of Water 'pumpedrby tween the pressure chamber 2 and the rotor 3, with a recess i arranged closely outside the latter and, extending concentrically i thereto, which recess extends in `one vertical Wallof the casing only to a portion of the thickness of the same, but passes entirely through the opposite wall. In this recess 4 the guide apparatus 5, 6, 'is insertedwhich consists of a ring 6 carrying blades or vanes 5 (Fig. 2). In4 order to retain the guide apparatus on the one hand in the pump casing 1,- and on the other hand to be able to take it out without taking apart the bearings or `other parts of the pump, the annular passage which passes through the wall of the casing,

vis closed by an annular cover 7 which bears against the free ends of the guide vanes or blades 5, and thereby shuts in or closes the guide apparatus on the side lying opposite to the-ring 6.

. l is the shaft of the rotor and 1c the suctionl pipe which communicates with the central part of' the rctor chaiii r on the side opposite to th it on which the annular cover is secured and the shaft l passes through this suction pipe; thus it will be seen-that the cover may easily be removed as there are no parts on the cover side of the casing which will interfere with its removal.

Now for each centrifugal pump several guide apparatus are prepared in order to allow of the pump being regulated so as toA deliver a given quantity of .water for a long period of time, the dimensions of the rings of which guide apparatus are similar to ene another, while the size of the admission oriiccs of the guide vanes in oneguide apparatus diff ers from those of theotlier guide apparatus. According to the quantity of water to be delivered each time, after the annular cover 7 has been taken away and the guide apparatus contained in the pump removed, another guide apparatus is inserted, the width of the guide vanes of which corresponds to the quantity of, Water iii question.

By the arrangement described the advantage is obtained that the pum is adapted to work with the highest .e 'eiency With either a smaller or a greater delivery than the norrnal quantity of Water.

Instead of the guide vanes being provided with a separate ring, which is only held by the annular cover, of course the guide vanes may also be directly mounted on the annular Cover, so that with the removal of the latterthe guide apparatus s also removed.

I declare that what I claim is:-

' l. A centrifugal pump comprising a casing having a rotor chamber therein and a pressure chamber, and an annular passage connecting the rotor chamber with the pressure chamber, said passage extending to the exterior of the casing, interchangeable guide blades adapted to be introduced into said passage, an annular removable cover for the passage, a rotor in the rotor chamber, a shaft therefor having one end mounted in the casing on the annular cover side thereof, and its other end extending through the other side of the casing, and a suction pipe communicating with the rotor chamber ,on

the side opposite to that 'on which the annular cover is secured.

2. A centrifugal pump comprising a easing having a rotor chamber and a pressure chamber, and an annular passage connecting the two chambers together, a removable an- 'iiular cover closing said passage, guide blades carried by said cover and extending into the passage, a rotor in the rotor Chamber, a shaft therefor, and a'suetion pipe communicating With said rotor chamber, said suction pipe and shaft being located on theside of the easing oppositeto that on which the annular passage is arranged.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

FRITZ NEUMANN.

Witnesses:

l/VILHELM ZAGHER, Jns'rus I IAVEMANN. 

